Process of ore flotation



Patented Aug. 1932 UNITED STATES PATENT OFFICE IRA II. IDERBY AND ORIND. CUNNINGHAM, OF INDIANAPOLIS, INDIAN. A,ASSIGNOI%S TO 1 I PETER C.REILLY, OF INDIANAPQIJIS, INDIANA I rnoc'nss or our: rno'rarron N0Drawing. 'Orig'inaI application filed March 19, 1926, Serial No. 96,061.Divided and this application filed December 30, 1930.

The present invention relates to improvements in ore flotation,including the flotation of sulfide ores, and other metalliferousmaterial, by the use of nuclear phosphorus compounds containing sulfur;that is, compounds structurally consisting of groups of atoms united toone or more phosphorus atoms as a nucleus, which compounds also containsulfur.

This application is a division of application Seiial No. 96,061 filed inour joint names on the 19th day of March, 1926, and is designed to coverspecifically flotation of ore or metallife ous material in the presenceof a flotation reagent or compound comprising a reaction product ofalcohol, phosphorus and sulfur, or stated in another way, an alcoholreconstructed with phosphorus and sulfur.

The invention is based upon our observation that organic compounds,which structurall consist of phosphorus as a nucleus to. W ich theradicals are attached, and which contain sulfur, areexcellent flotationagents and constitute-a class of compounds that have not heretofore beenused in the art of flotation.

Moreparticularly, our present invention embraces the products ofreaction of phosphorus sulfides (such as the trisulfide, P S orpentasulfide, P S with alcohols, and the use of such substances in oreflotation.

The reaction of the phosphorus sulfides, for exam'ple,phosphoruspentasul-fide, P 8 with Ialcohols, may result in the formation of asingle chemical substance with two or more phosphorus atoms'as a nucleusof the molecular structure, or there may .be a splitting of the moleculeof the phosphorus sul-' fide compound to'yield two or more prod-' ucts,each containing one ,or more phosphorus nuclear atoms, or the reactionmay or-may not mvolve the elimination of some of the sulfur of thephosphorus sulfide by the substitution of groups of atoms (radicals),the resulting product or products beingcharacterized, however, by thepresence of a nuclear phosphorus atom. or atoms and'the presence of.sulfur in ture. I

the molecular struc- Serial No. 505,666.

tive actionor collecting power for metalliferous materials, such assulfide minerals, 1n

These substances have a very high selec mineral flotation operations,but are lacking in frothing properties, so that any appropriate frothingagent (such, for example, as pine oil or tar acids), should baemployedin conjunction therewith in carrying out the flotation operation, It isnot necessary that chemically pure substances be used, since theunrefined products can be employed with metallurgical results equallygood 'to those with other oily materials, having flotation obtained withpure substances',.or practically value, or with solvent agents ormixtures of the same.. p

Generally stated it issufiicient to select the desired alcohol, and toreact thereupon with phosphorus pentasulfide or other sulfide ofphosphorus, or even With a mixture of phosphorus and sulfur, or in somecases with phosphorus and sulfur added,'separately in either order, thereaction being performed in a suitable container, and at a temperaturesuificiently high to cause reaction to take place.

For the preparation of the phosphbdizlfo compounds referred to we givethe following 1 specific example:

One part of powdered phosphorus pentasulfide, P LS is mixed with'threeto four parts of ethyl alcohol and the mixture is then heated to';7$);0., or thereabout, with constant stirring, and maintained at thistemperature until the 'P 'S has reacted with the alcohol to the extentthat it disappears in solution.'.

The product is'a clear liquid. a.

.--The proportion of alcohol in the above example corresponds to anexcess over that required for the reaction with phosphorus pentasulfide,the excess alcohol acting as a solvent or reaction medium which may berecovered,'preferably by vacuum distillation, since continued heating atelevated temperature carries the reaction too far.

- Instead of the procedure indicated-in the above example, the alcoholmay be brought up to the reaction temperature indicated and thephosphorus pentasulfide added slowly until the above proportion isobtained, or until no further reaction takes place. -7

f In the example given above, pure chemicals were used, but crudechemicals may be used with equally good results, except that it ispreferable to use anhydrous materials. We do not limit our claims to thequantity 10 of reacting substances herein named.

The general procedure indicated in the above example may be applied inchemically combining phosphorus pentasulfide with any of the alcoholsherein specified. In some in? stances heat may have to be applied tobring about the desired chemical combination, and in other cases thereaction mixture may desirably be cooled to carry on the reaction in thecold.

products in the above example from the solvents but to use the productin its unrefined condition. In most cases they are sufficiently solublein water so that in the flotation opera tion they are quickly dispersedas an aqueous solution throughout the pulp.

The products obtained by the reaction of the alcohols herein specifiedwith phosphorus pentasulfide as illustrated. in the above example, wereemployed in the flotation of a copper sulfide ore slime of the UtahCopper Company containing some copper oxides and analyzing about 0.9%copper, in the ratio'of one-tenth pound of product per ton of dry ore,

and tar acids as a frothing agent and a lime circuit being employed inconjunction therewith. The ore was subjected to the ordinary flotationoperation in a mechanical agitation type of flotation machine and atailing ana- 40 lyzing 0.06% copper was obtained, together with a highgrade concentrate analyzing about 20% copper, corresponding to arecovery of about 95% of the copper value in the ore under treatment.

In other examples we have used both smaller and larger amounts ofphosphosulfo compounds, in the flotation of ores, with satisfactoryresults, and we have also used phosphosulfo compounds both alone andwith 60 other flotation agents, with very satisfactory results.Furthermore, we do not limit our conditions for carrying out a flotationoperation to those included in the above example, but may use any typeof flotation machine, as for example, the Callow cell, or instead of analkaline circuit, we may use a'normal or acid circuit.

In this specification we havereferred to the I use of alcohol, such asethyl alcohol. It is to be understood, however, that other alcohols ormixtures thereof, such as denatured alcohol, methyl, propyl, and higheralcohols, can likewise bev employed.

What is claimed is f- 1. A process which comprises subjecting It ispreferable not to separate the reaction metalliferous material tofroth-flotation in the presence of a phosphorus sulfur compound of analcohol.

- 2. A process which comprises subjecting metalliferous material tofroth flotation while associated with a reaction product of a phosphoruscompound of sulfur with an alcoho of the herein described class. 1

3. In the art of froth flotation, the herein described step ofsubjecting metalliferous material to flotation in the presence of acompound formed by reacting phosphorus suifide with an unsubstitutedaliphatic alco o1.

4. In the art of froth flotation, the herein described step ofsubjecting material to flotation in the presence of a compound formed byreacting phosphorus sulfide with an unsubstituted aliphatic alcohol.

5. In the art of froth flotation, the herein described step ofsubjecting metalliferous material to flotation in the presence ofa'compound formed by reacting phosphorus sulfide with an unsubstitutedaliphatic alcohol containing not more than five carbon atoms.

6. In the art of froth flotation, the herein described step ofsubjecting metalliferous material to flotation in the presence of areaction product of phosphorus pentasulfide with ethyl alcohol.

7. A process which comprises the froth flotation of a metalliferousmaterial in the presence of a sulfur-phosphorus compound of an alcoholconsisting solely of carbon, hydrogen and oxygen.

In testimony whereof we have signed our names to this specification.

IRA H. DERBY. ORIN D. CUNNINGHAM.

